This research project is designed to evaluate a system for risk factor modification commencing soon after myocardial infarction (MI) that can be implemented on a wide scale. The Home Treatment Program (HTP) provides smoking cessation and diet/drug treatment of hyperlipidemia in the year after MI. Nurse-mediated interventions for smoking and hyperlipidemia commence on the 4th hospital day. The intensity of these interventions is tailored to the needs of individual patients. A project nurse maintains the continuity of the HTP primarily by means of systematic nurse-initiated telephone contacts with patients and, where necessary, by face-to-face contact with patients requiring special assistance in smoking cessation, and/or dietary management. Monitoring of patients' progress in the HTP is by patients' ratings on written status reports which are mailed to the project nurse at specified intervals Systematic feedback to patients based on their status reports is provided by computer- generated progress reports and nurse-initiated telephone contacts. Over a 30-month period 720 men and women recovering from MI in 4 Kaiser-Permanente hospitals in the San Francisco Bay area will be randomized to home-base programs for treatment of smoking and/or hyperlipidemia or usual care. Endpoints measured at the end of the first year and at the end of the study are smoking abstinence rate and total plasma cholesterol. The cost effectiveness of the HTP is enhanced by the efficiency of the monitoring and remediation system and by the availability of a comprehensive computerized database to guide the interventions. The ability of a single university research group to coordinate intervention for large numbers of patients treated in multiple hospitals further enhances the cost effectiveness of the study. The efficacy of this model of home-based medically-assisted self- care has already been demonstrated in programs for treatment of smoking and hyperlipidemia developed by the investigators. Demonstration of the success of this new cost-effective system for multifactorial risk factor modification will lay the groundwork for an expanded study evaluating the effect of risk factor modification on morbidity and mortality in post-MI patients.